US4657808A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Activated carbon products and their manufacture
Assignee: Charcoal Cloth Ltd
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Filing: 1985-03-19
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Granted: 1987-04-14
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Expires: 2005-03-19
Abstract
Abstract An activated carbon product such as a charcoal cloth or felt has, in addition to any activating material, a metal uniformly dispersed therein. The metal may be catalytic or bactericidal, and a particularly preferred product of the invention contains silver and is suitable for use as a surgical dressing. Such products can be produced by a conventional activation procedure using a mixture of halides, even if the further metal halide is substantially insoluble in the impregnation solution used for activation, by incorporating in the solution ammonia and a sequestering agent such as citric acid.
Inventors
- 👤 Frederick A. P. Maggs
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:51
CPC Classifications
A; A61; A61L; A61L15/00; A61L15/16; A61L15/42; A61L15/46; A61F; A61F13/00; A61L15/18; C; C01; C01B; C01B32/00; C01B32/30; C01B32/354; C01B32/382; A61F2013/00361; A61F2013/00902; A61F2013/00936; A61L2300/00; A61L2300/10; A61L2300/102; A61L2300/104; A61L2300/108; A61L2300/40; A61L2300/404; Y; Y10; Y10S; Y10S428/00; Y10S428/913; Y10T; Y10T428/00; Y10T428/30; Y10T442/00; Y10T442/30; Y10T442/3382; Y10T442/40; Y10T442/475; Y10T442/50; Y10T442/57; Y10T442/60; Y10T442/654; Y10T442/658
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
39 words
A surgical dressing which consists essentially of an activated charcoal cloth or felt having uniformly dispersed therein at least one first activating metal element selected from Zn, Al, Ca, Mg and Fe, and Ag as a second metal element.
Claim 2
Dependent Claim
39 words
A surgical dressing which consists essentially of an activated charcoal cloth or felt having uniformly dispersed therein at least one first activating metal element selected from Zn, Al, Ca, Mg and Fe, and Ag as a second metal element.
Claim 3
Dependent Claim
21 words
A surgical dressing according to claim 1 in which the amount of silver is from 0.1 to 1 percent by weight.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-04-13 | 1990-10-13 | 1991-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-04-13 | 1994-10-13 | 1995-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-04-13 | 1998-10-13 | 1999-04-14 | $7700.00 | Window Closed / Lapsed |